1. Field of the Invention:
This invention relates to an information signal transmitting device for transmitting information, for example, in the form of identification codes between a movable unit mounted on a movable element such as a pallet on a production line of a factory or a work on such a pallet and a fixed unit mounted on a fixed element in an opposing relationship to the movable unit.
2. Description of the Prior Art:
One of conventional information signal transmitting devices of the type mentioned which are used commonly is such an information signal transmitting device of the mechanical type as shown in FIG. 6. Referring to FIG. 6, the information signal transmitting device shown includes a combination of a movable unit 33 including a block 31 secured to a pallet P on a conveyor C and a plurality of storage pins 32 made of a metal and supported for movement on the block 31 such that they may be individually pushed in or pulled out on the block 31, and a reader 35 including a plurality of contactless switches 34 disposed along the conveyor C such that they may face to the respective storage pins 32 at a predetermined stopping position of the pallet P. The storage pins 32 are selectively set in position by means of a pin setting device 39 which includes a plurality of air cylinders 37, a storage pin pushing and drawing piece 36 provided at an end of a rod of each of the air cylinders 37, and a solenoid valve 38 for driving each of the air cylinders 37.
Since the conventional device, however, is of the structure wherein the storage pins 32 are slidably moved, abrasion occurs readily at sliding portions of the storage pins 32 and at contacting portions of the pin setting device 39 with the storage pins 32, which will deteriorate operation of the storage pins 32, make the structure of the entire device complicated and cause the device to require an increased installation spacing. Particularly where the number of the storage pins 32 is increased in order to increase the amount of information to be stored, a large occupation spacing is required.